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sulcus

[suhl-kuh s]
noun, plural sul·ci [suhl-sahy] /ˈsʌl saɪ/.
  1. a furrow or groove.
  2. Anatomy. a groove or fissure, especially a fissure between two convolutions of the brain.

Origin of sulcus

1655–65; Latin: furrow
Related formssub·sul·cus, noun, plural sub·sul·ci.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

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British Dictionary definitions for sulcus

sulcus

noun plural -ci (-saɪ)
  1. a linear groove, furrow, or slight depression
  2. any of the narrow grooves on the surface of the brain that mark the cerebral convolutionsCompare fissure

Word Origin for sulcus

C17: from Latin
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for sulcus
n.

plural sulci, Latin, literally "furrow, trench, ditch, wrinkle."

Online Etymology Dictionary, © 2010 Douglas Harper
sulcus in Medicine

sulcus

[sŭl′kəs]
n. pl. sul•ci (-kī, -sī)
  1. Any of the grooves on the brain surface, bounding the gyri; a fissure.
  2. A long narrow groove or depression, as in an organ or a tissue.
Related formssul′cal adj.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.